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61.
62.
Transneuronal degeneration of retinal ganglion cells was directly demonstrated in a patient who had unilateral removal of the striate cortex forty years prior to necropsy. For comparison, another case is presented showing anterograde transneuronal atrophy forty years after enucleation of one eye.  相似文献   
63.
CT evaluation of complications of abdominal aortic surgery   总被引:5,自引:0,他引:5  
Mark  A; Moss  AA; Lusby  R; Kaiser  JA 《Radiology》1982,145(2):409
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Thyroid scintigraphy using Tc-99m pertechnetate is a frequently performed procedure in routine nuclear medicine practice. The indications for thyroid scintigraphy are investigation of hyperthyroidism, nodularity of the gland, cause of thyroid stimulating hormone elevation and localization of an ectopic thyroid gland. In the pediatric population, the most common request is for the evaluation of neonatal hypothyroidism. This imaging procedure is helpful in the identification of the underlying cause as well as in making a differential diagnosis. Early diagnosis is essential for appropriate therapy planning in this age group, and thyroid scintigraphy provides important diagnostic data. This article is written to review the scintigraphic findings in various congenital thyroid anomalies and to underline its use in the differential diagnosis.  相似文献   
66.
Longitudinal growth changes in the transverse and vertical craniofacial dimensions occurring between 10 and 14 years of age were evaluated in 22 female and 23 male subjects. All subjects were healthy, had a clinically acceptable occlusion, and had not received orthodontic or orthopedic therapy before. Serial cephalometric radiographs were taken at ages 10, 11, 12, and 14 years. In studying the P-A cephalograms, seven transverse and five vertical measurements were used. The effects of age and sex on the transverse and vertical growth of the craniofacial structures were investigated by means of analysis of variance and Bonferroni multiple comparison test. The results of the study revealed that all measurements studied were affected by age, and cranial, facial, nasal, and maxillary widths were affected by sex. The most pronounced age-related increases occurred in the mandibular width for transverse measurements and in the total facial height for vertical measurements in both sexes during this study.  相似文献   
67.
Neonatal tetanus is an important health problem with an estimated 500,000 deaths per year worldwide, particularly in developing countries. We analysed 56 cases of neonatal tetanus (NNT), retrospectively, who were admitted to Diyarbakir Children State Hospital between 1994 and 2001. In 1998 an intervention in a childcare intensive unit was conducted, which included a nurse education programme, increasing the number of nurses and other health staff, and more qualified management of cases. The mean age of patients was 7.9 days at admission, and the male:female ratio was 1:6. Eleven per cent of the cases had body weight under 2500 g. The mean hospitalization period was 9.9 days. All patients were born at home without medical help and 28.6 per cent were from urban areas. The case fatality rate that was formerly 88.5 per cent, decreased to 53.6 per cent by the intervention conducted in 1998. Based on our findings, we can say that improved hospitalization conditions and intensive care may reduce mortality. Enforcing preventive policies both in rural and urban areas is of great importance in the least developed regions.  相似文献   
68.
The purpose of this study is to evaluate the possible reasons of an observation of diminished uptake of Tc-99m MIBI in the early phase of parathyroid scintigraphy in the thyroid and parathyroid glands in patients with chronic renal failure who are being evaluated for hyperparathyroidism. Fourteen patients with secondary hyperparathyroidism all on hemodialysis with supplement therapy consisting of mainly vitamin D and calcium carbonate were studied. Neck and mediastinum images obtained at early and late phases were evaluated both visually and semiquantitatively. Patients with high PTH levels on hemodialysis showed diminished accumulation of radioactivity in the thyroid glands in the early phase compared to the soft tissue with a ratio of 1.54 +/- 0.39 (mean +/- std). A control group consisting of 10 patients with osteoporosis and Rickets' disease on vitamin D therapy was taken as control group A, as well as 11 patients with no problems other than cardiac who were not on any medication as control group B and 8 patients on hemodialysis only with normal PTH levels as control group C. Patients in control group A and C showed diminished accumulation of radioactivity in the thyroid glands in the early phase compared to the soft tissue with a ratio of 1.57 +/- 0.43 and 1.34 +/- 0.13, respectively, while patients in control group B showed good uptake 3.18 +/- 0.43. None of the studies showed parathyroid pathology. The results of this study show that patients with chronic renal failure under hemodialysis treatment are prone to show decreased uptake of the radioactivity. Another finding is that vitamin D supplements can cause diminished uptake of Tc-99m MIBI. A possible explanation is mentioned in the literature by an increase in PGP level and multi-drug resistance, so we suggest that it may play a role in impaired Tc-99m MIBI uptake in the thyroid phase and recommend cessation of vitamin D3 metabolites before performing parathyroid scintigraphy.  相似文献   
69.
Primary cerebral neuroblastoma: a case report and review   总被引:3,自引:0,他引:3  
Primitive neuroepithelial tumors are the least common among supratentorial tumors in children. They pose great diagnostic difficulty, preoperatively as well as pathologically. Being quite rare, cerebral neuroblastomas are accepted as a distinct pathological entity, which differs from other neuroectodermal tumors, although clinically, radiologically, and morphologically at operation they are indistinguishable. Also differentiation between primary cerebral neuroblastoma and the other primitive neuroectodermal tumors may be difficult on light microscopy and be misleading. A 9-year-old girl with primary cerebral neuroblastoma who was initially misdiagnosed is reported. The other cases from the literature are reviewed and the nature of this rare tumor and its differential diagnosis is discussed.  相似文献   
70.
OBJECTIVE: Former studies have pointed out that hemodynamic stress imposed by associated valvular disease is the primary factor in the development of ascending aorta dilatation. At present, intrinsic wall pathology is blamed for dilatation and aneurysm formation in bicuspid aortic valve (BAV). MATERIALS AND METHODS: Aortic valve replacement (AVR) was performed on 78 adult patients with BAV. Patients were divided into two groups. Group I (n = 27) underwent only AVR. Group II (n = 51) underwent AVR and additional ascending aorta procedures such as Shawl-Lapel aortoplasty (n = 12) and tailoring aortoplasty (n = 9). Dacron wrapping was performed after both techniques were done. Ascending aorta replacement was done on 11 patients by using composite graft. Supracoronary graft replacement was performed in 3 patients after AVR. RESULTS: Ascending aorta diameter increment was 1.25 mm/year in normotensive and 2.80 mm/ year in hypertensive patients. Ascending aorta aneurysm (diameter > 55 mm) developed in eight patients in the postoperative period in group I. Ascending aorta dilatation did not develop in group II patients. Mean survival time +/- standard error (SE) was 128 +/- 11 and 99 +/- 4 months and survival possibility was 77.78% and 92.16%. Freedom from reoperation was 65.4% and 95.9% in 8 years in group I and group II, respectively. CONCLUSION: Aortic wrapping with or without aortoplasty has a beneficial effect not only in dilated ascending aorta but also in all nondilated BAV patients with normal-sized aortic diameter. Ascending aorta wrapping in BAV patients preserves the endothelial lining and prevents further dilatation, aneurysm formation, and dissection.  相似文献   
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